Airworthiness Directives; Bombardier Model CL-215-6B11 (CL215T Variant), and CL-215-6B11 (CL415 Variant) Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Bombardier Model CL-215-6B11 series airplanes, that currently requires inspections to detect cracking in the rear engine mount struts, and replacement of struts with new struts, if necessary; and the eventual replacement of all struts with new struts. This amendment requires adding repetitive detailed inspections to detect cracking in the rear engine mount struts and replacement of struts with new struts, if necessary. This amendment also expands the applicability of the existing AD and makes the replacement of all struts with new, machined struts an optional terminating action for the repetitive inspections. The actions specified by this AD are intended to prevent failure of the rear engine mount struts, which could subsequently result in reduced structural integrity of the nacelle and engine support structure. This action is intended to address the identified unsafe condition.